Available Configurations
Type R: Monitoring High Level Dose Rates A monitor scaled over the range 0.5 to 5000 μSv h-1 (0.05 to 500 mR/h). The G-M tube is compensated to give a useful response from 45 keV to
1.5 MeV and above. It is not recommended for monitoring X-radiation from apparatus operating below 75 kVp.

Type G: Monitoring for Low Environmental Dose Rates Highly sensitive performance. The monitor is scaled over the range 0.05 to 75 μSv h-1 (0.005 to 7.5 mR/h). The useful energy range is 55 keVto 1.5 MeV and above. This instrument is not suitable for monitoring X-radiation.

Type D: A monitor using a partially compensated G-M tube to obtain an extended low energy response.
The instruments is scaled over the range of 0.5 to 1000 μSvh-1 (0.05 to 100 mR/h). The useful energy range is from 30 keV to 1.5 MeV but response is maintained down to at least 17 keV. It is suitable for measuring radiation from X-ray apparatus operating at or above 45 kVp.

Type X: This instrument is scaled 0.5 to 2000 counts per second and uses an end window G-M tube without energy compensation. It is sensitive to radiation down to 10keV and is therefore useful for locating X-ray leakage from a variety of systems including high voltage equipment where X-rays are generated adventitiously. It is not intended for measurement but as a relative check device.